<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>css边框属性</title>
    <style type="text/css">
        #div-box{
            width:300px;
            height: 300px;
            /*
            solid 实线
            */
            border: 4px outset red;
        }
    </style>
</head>
<body>
<div id="div-box">hello,world!</div>
</body>
</html>